Orthopedic implants are sometimes fabricated to include porous surfaces or surface treatments that allow bone tissue to form within the porous structure after implantation and help fuse an implant with the bone to which it is attached. Material selection for such implants has been somewhat limited by the particular combination of desirable material properties, such as high tensile strength, fatigue strength, strength-to-weight-ratio, flexibility, toughness, wear resistance, and biocompatibility. Some of these material properties must also be taken into consideration when selecting surface treatments and the types of processes used to apply surface treatments. Where surface treatments include coatings, it may also be important to select implant and coating materials and processes that are capable of forming high strength bonds with each other. Certain thermal spraying methods may be used to apply coatings to orthopedic implants. But some of these methods may tend to impart impurities to the resulting coating, particularly where the coating material is reactive with atmospheric gases at high temperatures.